Built-in flash system

ABSTRACT

A built-in flash system is disclosed which includes a housing chamber provided in the upper front of a penta-house of a finder optical system, and a casing provided in the housing chamber and having a flashlight emitter arranged so as to be movable between a projecting position where the casing is projected for light emission and a housing position where the casing is housed in said housing chamber, the casing is arranged to be moved between the projecting position and the housing position by a linkage mechanisms disposed at sides of said built-in flash system.

This is a continuation of pending prior parent application Ser. No.07/626,230 filed on Dec. 11, 1990, abandoned, which is a continuation ofapplication Ser. No. 07/490,001filed Mar. 7, 1990, abandoned, which is aDivisional of application Ser. No. 07/306,436, filed Feb. 3, 1989, nowU.S. Pat. No. 4,920,368, which is a continuation of 07/143,488, filedJan. 13, 1988, abandoned.

BACKGROUND OF THE INVENTION

The present invention relates to a camera having a built-in flash.

Recently, with the progress of automatic mechanization in the field ofsingle-lens reflex cameras, various cameras including an autofocusingdevice and a built-in flash have been proposed. An example of such anautofocusing device is described in U.S. Pat. No. 4,801,963 to Koyama etal, wherein the focus condition of the camera lens is determined basedon the contrast of an image transmitted through the lens of thepositional relationship (often referred to as a phase difference)between images or image portions transmitted through the lens. If thelighting conditions or object contrast are low, there may beinsufficient light or insufficient contrast for the image sensors tooperate effectively. Accordingly, Koyama et al provides an auxiliarylight projector for radiating a contrast pattern (stripe pattern) towardthe object during conditions of low light or low contrast. However,Koyama et al provides the auxiliary light projector separately, andtheir remains a problem as to how to secure a space for the auxiliaryspotlight projector in the single-lens reflex camera having a limited inspace.

Also, a single-lens reflex camera has an object within a range of from aclose-up distance to an infinite distance as its aim. An optimumfocal-length lens is selected corresponding to the kind of the subjectand the distance from the subject. The cylinder length of theinterchangeable lens is enlarged corresponding to the focal lengththereof. Recently, with the advance of zoom lenses, photographersordinarily using such zoom lenses to cover from wide-angle lenses totelephoto lenses, instead of conventional fixed-focal-lengthinterchangeable lenses, have increased in number. Generally, the minimumcylinder length of the zoom lens is at the maximum focal length.Accordingly, if the zoom lens is shifted to the minimum focal length,the cylinder length is not so shortened.

Therefore, in the case where a built-in flash mechanism is incorporatedin a single-lens reflex camera, it becomes important to design thecamera to prevent flashlight from being blocked by the lens cylinder.

Also, in a conventional built-in flash, the flash is held in the housingposition by a lock mechanism for causing a pin provided the flash or onthe linkage mechanism to engage with a hook provided on the camera body.However, the lock mechanism has a disadvantage as follows. When pressureis applied to the light emission portion to move down to the housingposition and then released after the pin has engaged with the hook, thelight emission #portion slightly moves in the direction reverse to thepressure or in other words slightly returns toward the projectingposition because a clearance always arises between the pin and the hook.For this reason, a slight space arises between the opening line portionof the housing chamber and the ceiling plate.

Such a space gives the user an unfavorable impression of the outsideappearance and handling properties of the camera as a precision machine.

Also, three are two types of built-in flashes in cameras, that is, ofthe stationary type and of the housing type. The conventional housingtype built-in flash is arranged such that a flash unit urged by a springmeans in

the direction of projection is normally kept at a housing position by astoppage/engagement means so that the flash unit can be moved to aprojecting position by removing the stoppage/engagement in use.Therefore, a shock due to projection was unavoidable and, further, goodoperational feeling could not be attained. In addition, there is nodenying the fact that the shock has a bad influence upon the camerawhich is a precision instrument. In addition, according to theconventional housing type built-in flash, the light emission surface ofthe flash unit could not be moved to the bouncing position where thelight emission surface looked more upward than the direction toward thesubject. If bounce-photographing was necessary, it was necessary to useanother outside flash.

SUMMARY OF THE INVENTION

In view of the above problems, an object of the invention is to providea camera in which a large space is not necessary for providing theauxiliary spotlight projector.

On the basis of the fact that the auxiliary spotlight projector is usedin the case of low illuminance or low contrast and that the built-inflash is used mainly in the case of low illuminance, the presentinvention is particularly characterized in that the auxiliary spotlightprojector is provided adjacent to the flash of the built-in flash deviceheld by the pop-up mechanism selectively in the housing position and inthe projecting position.

In the case where the auxiliary spotlight projector provided adjacent tothe flash is held by the pop-up mechanism selectively in the housingposition and in the projecting position together with the flash, notonly is it easy to secure a space for housing the auxiliary spotlightprojector but also it is easy to handle because the auxiliary spotlightprojector and the flash can be used at the same time. In addition, thecamera can have an aesthetic or smart appearance, because the auxiliaryspotlight projector and the flash can be held in the housing positionwhen unused.

Another object of the invention is to provide a built-in flash which issimple in construction, sure in operation and easy in locating the flashitself in a higher and more advanced light emission position.

On the basis of a conclusion that a turn mechanism by four-point linkageis suited for-the mechanism for popping up this type built-in flash, thepresent invention has been completed. That is, the built-in flash pop-upmechanism according to the present invention is characterized in thatthe casing is arranged to be moved between the projecting position andthe housing position by a pair of four-point linkage mechanisms disposedat the left and right sides of the built-in flash, each of thefour-point linkage mechanisms being constituted by two pairs of frontand rear turning levers, each pair of the front and rear turning leversbeing pivoted at their respective one ends to a corresponding one ofopposite sides of the housing chamber and pivoted at their other ends tofront and rear portions on a corresponding one of opposite sides of thecasing. This mechanism is very simple in construction and therefore isadvantageous in that the number of parts is small, the workability inassembling is good, the operation is sure, etc. In addition, the requestthat the flash must be located in a higher and more advanced projectingposition can be attained easily.

Still another object of the invention is to provide a lock mechanism forlocking a pop-up device, so that the housing chamber is tightly coveredwith the ceiling plate of the flash when the flash is in the housingposition to thereby prevent any space from arising between the ceilingplate and the opening of the housing chamber or to prevent the ceilingplate from floating up from the housing chamber.

To attain the foregoing object, the present invention is directed to abuilt-in flash of the type having a turning lever which moves as a flashmoves between a projecting position and a housing position,characterized in that a lock lever having a top stoppage/engagementsurface arranged to engage/disengage with/from a stoppage surface of theturning lever moved to the flash-housing position is pivoted to thehousing chamber, in that a top stoppage/engagement surface of the locklever is formed as a wedge surface having a wedge function when theturning lever is moved toward the flash-housing position, and in thatthe lock lever is arranged to be operated to move in the axial directionof a shaft of the turning lever so as to make the topstoppage/engagement surface of the lock lever to engage/disengagewith/from the stoppage/engagement surface of the turning lever.

Still another object of the invention is to provide a built-in flashmechanism in which the flash unit is arranged to be movable between theprojecting position and the housing position without generating anyshock to thereby attain an operational feeling of high rank, and inwhich the flash unit is made movable further to the bouncing positionwhere the light emission surface of the flash unit looks more upwardthan the direction toward the subject.

The present invention has been perfected based on the thought that theflash unit which has had conventionally to be moved to the projectingposition by spring means is continuously driven by an electric motor. Inother words, according to the present invention, in a built-in flash,there is provided a flash unit disposed at an upper portion of thecamera and arranged to be movable between a normal light emissionposition where a light emission surface looks forward a subject and ahousing position where the light emission surface looks more downwardthan the direction toward the subject, the flash unit being moved by anelectric motor between the normal light emission position and thehousing position. Preferably, the flash unit can be made movable furtherto a bouncing position where the light emission surface looks moreupward than the direction toward the subject, so that if the flash unitis moved by the electric motor among the bouncing position, the normallight emission position, and the housing position to thereby make itpossible to perform bounce-photographing.

An object of the present invention is to provide a built-in flashapparatus of the housing type and having an adjustable radiation angle,in order to solve the problem in the conventional built-in flash.

Another object of the present invention is to provide a built-in flashapparatus in which a flash unit is arranged to be movable between aprojecting position and a housing position without generating any shockto thereby attain a desirable operational feeling.

According to the present invention, in a built-in flash apparatus in acamera, there are provided a flash unit disposed at an upper portion ofthe camera and arranged to be movable between a normal light emissionposition where a light emission surface is exposed and a housingposition where the light emission surface is not exposed, and aconverging lens body provided in front of the light emission surface ofthe flash unit and arranged so as to be movable together with the flashunit between the normal light emission position and the housingposition, the distance between the converging lens body and the flashunit in the normal light emission position being made variable.Preferably, the flash unit and the converging lens body are moved by anelectric motor, so that no shock is generated in movement of the flashunit and the converging lens body between the normal light emissionposition and the housing position and a desirable operational feelingcan be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

FIG. 1 is a partly perspective view showing a lighting portion of abuilt-in flash as a first embodiment according to the present invention;

FIG. 2 is a front view showing the built-in flash united into asingle-lens reflex camera body having an autofocusing device;

FIG. 3 is a partly vertical section taken along the optical axis, of thecamera body showing the condition in which the built-in flash is housed;

FIG. 4 is a partly vertical section showing the condition in which thebuilt-in flash is projected;

FIGS. 5 and 6 illustrate an auxiliary spotlight projector optical systemsuitable for the camera according to the invention;

FIG. 7 is a partly vertical section in a housing condition according toa second embodiment

FIG. 8 is a partly vertical section in a projecting condition;

FIGS. 9 and 10 are a perspective view and a sectional view showing anexample of a lock mechanism;

FIG. 11 is a perspective view showing the form of the back of thehousing chamber;

FIG. 12 is a view for explaining the relation between the range offlashlight by the built-in flash and the range of photographing by thecamera lens;

FIGS. 13 and 14 are vertical sections in a housing condition and in aprojecting condition respectively showing a camera having a built-inflash as a third embodiment according to the present invention;

FIG. 15 is a front view showing the outside appearance of the camera;

FIGS. 16 and 16a are partly perspective views showing a fourthembodiment of the built-in flash apparatus in a camera according to thepresent invention;

FIGS. 17 and 18 are sectional views of the flash unit, in the normallight emission position and in the housing position, respectively,according to fifth embodiment; and

FIG. 19 is a partly plan view of the built-in flash apparatus.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention will hereunder be described with reference to thedrawings.

FIG. 1 is a partly perspective view showing a lighting portion of abuilt-in flash as a first embodiment according to the present invention;FIG. 2 is a front view showing the built-in flash incorporated into asingle-lens reflex camera body having an autofocusing device; and FIGS.3 and 4 are partly vertical sections, of the camera body showing thepop-up mechanism of the built-in flash.

A casing 20 of the built-in flash according to the invention ispartitioned into two boxes 21a and 21b, so that a flash F is provided inone box 21a, and an auxiliary spotlight projector S for measuringdistance is provided in the other box 21b. A diffusion lens 22 ismounted to the front of the box 21a, and a xenon tube (light emissiondevice) 23 and a reflection mirror 24 are attached to the rear of thebox 21a. A converging lens 25 formed together with the diffusion lens ismounted to the front of the box 21b, and a spotlight projector 26 forradiating a stripe pattern to measure distance is attached to the rearof the box 21b.

The casing 20 is attached to a housing chamber 16 provided in apenta-house 12 of a camera body 10 through a pop-up mechanism so thatthe casing 20 is movable between the projecting position and the housingposition. The structure will be described in detail with reference toFIGS. 3 and 4.

The housing chamber 16 for housing the casing 20 is provided to theupper front of a penta-prism 14 which is housed in the penta-house 12.The casing 20 has a ceiling plate 27 which forms a closed appearancetogether with the penta-house 12 when the casing 20 is put in thehousing chamber 16.

A pop-up linkage means is provided between side plates 28 and walls ofthe housing chamber 16, the side plates 28 being disposed at the leftand right of the casing 20. The structure in the left side is the sameas that in the right side. Hereinafter, the invention will be describedabout one side. Shafts 34 and 40 are respectively inserted into holes28a and 28b formed in the side plate 28. A first lever 32 and a secondlever 38 are rotatably supported on the shafts 34 and 40, respectively.The other ends of the first and second levers 32 and 38 are respectivelyattached to the penta-house 12 within the housing chamber 16 through theshafts 36 and 42 to thereby form a pop-up mechanism composed of four-barlinkage for the casing 20. The shaft 36 supports the U-shaped firstlever 32 at the bent portion thereof. A torsion spring not shown isattached to the shaft 42 of the second lever 38, so that the secondlever 38 is urged to move counterclockwise in the drawing or in otherwords the casing 20 is urged to move upward and forward.

Further, a lock lever 50 is rotatably supported by the shaft 42, and oneend of the torsion spring is fitted to the shaft 42 so that the locklever 50 is urged to move clockwise normally. However, the range ofmovement of the lock lever 50 is limited by contact between one portionof the lock lever 50 and the inner wall of the housing chamber. When thecasing 20 is put in the housing chamber 16, the top end of the locklever 50 is engaged with a lock surface 32a of the first lever 32 toprevent the first lever from turning counterclockwise, so that thecasing 20 is held in the housing position by the force of the torsionspring so as not to be moved to the projecting position.

The engagement of the lock lever 50 with the lock surface 32a isreleased by moving the lock lever 50 perpendicularly to the paperthrough an unlock member not shown, attached to a side of thepenta-house 12.

According to the aforementioned built-in flash, when the casing 20 ismoved to the projecting position by the operation of the unlock member,the flash F and the auxiliary spotlight projector S are both exposed atthe same time as shown in FIGS. 1 and 3. In this condition, preparationfor lighting in the xenon tube 23 of the built-in flash is started and,on the other hand, preparation for spotlighting in the spotlightprojector is finished. If the photographer now pushes down the releasebutton of the camera body 10, the spotlight projector 26 is energized toradiate a stripe pattern and then the distance from the subject isdetected within the camera body 10 by reference to the contrast of thesubject corresponding to the stripe pattern. Next, the lens is moved tothe focusing position based on the distance-detection signal. If therelease button is more pushed down, a series of procedures, such asmoving-up of the mirror, running of the focal plane and flashing of thexenon tube 23, are perfected.

The aforementioned operating method applies to the case where the flashunit F and the auxiliary spotlight projector S are used at the sametime, that is, the case of low illuminance. In practice, this methodwill be used most frequently. Accordingly, the built-in flash is easy tohandle. It is a matter of course that the auxiliary spotlight projectorS can be singly used in the case of low contrast. In this case, a switchmay be provided to stop the operation of the flash F in spite ofpopping-up of the casing 20.

In this invention, the kind and position of the mechanism for popping-upthe casing are not limited. For example, the mechanism may be providedat a grip portion, at a film take-up portion or the like in the camerabody 10. In this case, the pop-up mechanism may be movable vertically sothat She flash F and the auxiliary spotlight projector S can be arrangedvertically.

FIGS. 5 and 6 show in a side and a perspective view, respectively, thepreferable configuration of an optical system in a focus detectingauxiliary light projecting apparatus, that is, the auxiliary spotprojector S shown in FIGS. 1 and 2, according to the present invention.It is intended that the apparatus is applied to a camera equipped with aTTL-type AF system.

In these figures, an imaging lens 51 is included in the camera. In orderfor the image of an object (not shown) to be formed in focus on a filmsurface 52, the imaging lens 51 is adapted to be driven from theposition indicated by the solid line to the position indicated by eitherthe one-long-and-two-short dashed line or the dashed line in response tothe result of focus detection.

The imaging lens 51 also serves as a lens in the focus detecting systemsuch that part of the light emanating from the object passing the lens51 is reflected by a movable mirror into a focus detecting apparatuswhich may operate on a variety of principles of focus detecting such asby detection of contrast or by detection of phase difference. The outputof the focus detecting apparatus is used by a known lens drive circuitto translate the imaging lens 51 along the imaging optical axis L₁ -l₂to bring the imaging lens 1 into focus with the object.

Above the imaging lens 51 is disposed, as shown in FIG. 5, a projectionoptical unit S which makes up a focus detecting auxiliary lightprojecting apparatus. The optical unit S is an integral assembly of aprojection lens 54, a patterned surface 55 and a light source 56. Thelayout and configurations of the individual components of the opticalunit 53 are described below. First, the projection lens 54 is sopositioned that its optical axis l₁ -l₂ is inclined to the optical axisL₁ -L₂ of the imaging lens 51, with the two optical axes intersectingeach other at a point C₁. The patterned surface 55, the lighttransmitting parts of which diffusely pass the light from the lightsource 56, is inclined to a plane 54 a which passes through theprojection lens 54 and which intersects its optical axis l₁ -l₂ at aright angle. The projection optical unit 53 taken generally forms atilting optical system. It is generally known that when an object planeis inclined with respect to a plane through a lens that intersects itsoptical axis, the resulting image plane is spatially inclined withrespect to the object plane in accordance with the law of Schib-Lief.Therefore, in the light projecting optical unit S, too, a patternedimage plane 55' which is a conjugate surface with respect to thepatterned surface 55 will form (i.e., will be focused) in a spatiallyinclined manner with respect to the patterned surface 55, as shown inFIG. 6.

In the embodiment shown, the imaging lens 51 is so positioned that itsoptical axis L₁ -L₂ will partially lie in the patterned image plane 55'.Consequently, the extension of the plane 54a which crosses theprojection optical axis l₁ -l₂ at a right angle will intersect theextension of the patterned surface 55 at a point C_(o) which is locatedon the optical axis L₁ -L₂ of the imaging lens 51.

Light issuing from the light source 56 disposed in the back of thepatterned surface 55 passes through the patterned surface and the imagesof points P₁ to P₄ on the patterned surface 55 are formed at respectivepoints P₁ ' to P₄ ' on the patterned image plane 55', in such a mannerthat the pattern of alternating clear and opaque lines in the surface 55will align on the plane 55' in a direction parallel to the imagingoptical axis L₁ -L₂. In the embodiment, red light which is in thewavelength region of low luminosity where the human eye is practicallyinsensitive.

In the auxiliary spotlight projector S described above, if the object issituated on the patterned image plane 55', a sharp patterned image ofgood contrast can always be projected irrespective of the distance tothe object.

The patterned image plane 55' can be enlarged by increasing the size ofthe patterned surface 55 and if its size is increased and a brighterillumination provided by the light source 56, the range of focusdetection can be extended to the farthest point that is permissible bythe detection capacity of the optical unit 53.

Focus detection, whether it is achieved by the active or passive method,is directed to only part of the imaging range, which is generallyreferred to as the distance measuring zone. In the embodiment beingconsidered, this distance measuring zone is set to lie in theneighborhood of the optical axis L₁ -L₂ of the imaging lens. Therefore,in the embodiment described above, the optical axis L₁ -L₂ of theimaging lens 51 is situated on the patterned image plane 55' in order toenable precise focus detection and focus adjustment.

The apparatus according to the embodiment described above can befabricated in a compact size because the single light projecting opticalunit S is capable of covering any of the objects that are within thedistance metering zone, which if fairly large. As a further advantage,this unit which is an integral combination of the projection lens 54,patterned surface 55 and the light source can be readily assembled intothe camera body such as to satisfy the requirements for the layoutspecified by the present invention.

It is apparent from description of the invention that the auxiliaryspotlight projector for radiating a contrast pattern to measure distanceis provided adjacent to the flash of the built-in flash provided to thecamera body through the pop-up mechanism. Accordingly, it is notnecessary that the auxiliary spotlight projector is provided separatelyfrom the flash. Further, if the auxiliary spotlight projector formeasuring a distance and the flash are to be used at the same time inthe case where the subject is too dark enough to attain contrast, thetwo can be located in the projecting position at the same time.Accordingly it is easy to handle.

Also a single-lens reflex camera has a subject within a range of from avery near distance to an infinite distance as its aim. An optimumfocal-length lens is selected corresponding to the kind of the subjectand the distance from the subject. The cylinder length of theinterchangeable lens is enlarged corresponding to the focal lengththereof. Recently, with the advance of zoom lenses, photographersordinarily using such zoom lenses to cover from wide-angle lenses totelephoto lenses, instead of conventional fixed-focal-lengthinterchangeable lenses, have increased in number. Generally, thecylinder length of the zoom lens is determined by the maximum focallength. Accordingly, if the zoom lens is shifted to the site of theminimum focal length, the cylinder length is not so shortened.

Therefore, in the case where a built-in flash mechanism is incorporatedn a single-lens reflex camera, it becomes important to design the camerato prevent flashlight from being blocked the lens cylinder.

Another object of the invention is to provide a built-in flash which issimple in construction, sure in operation and easy in locating the flashitself in a higher and more advanced light emission position.

On the basis of a conclusion that a turn mechanism by four-point linkageis suited for the mechanism for popping up this type built-in flash, thepresent invention has been completed. That is, the built-in flash pop-upmechanism according to the present invention is characterized in thatthe casing is arranged to be moved between the projecting position andthe housing position by a pair of four-point linkage mechanisms disposedat the left and right sides of the built-in flash, each of thefour-point linkage mechanisms being constituted by two pairs of frontand rear turning levers each .pair of the front and rear turning leversbeing pivoted at their respective one ends to corresponding one ofopposite sides of the housing chamber and pivoted at their other ends tofront and rear portions on corresponding one of opposite sides of thecasing. This mechanism is very simple in construction and therefore isadvantageous in that the number of parts is small, the workability inassembling is good, the operation is sure, etc. In addition, the requestthat the flash must be located in higher and more advanced projectingposition can be attained easily.

A second embodiment of the present invention will be described withreference to FIGS. 7 to 11. FIGS. 7 and 8 show and embodiment of thebuilt-in flash pop-up mechanism according to the present invention, inwhich FIG. 7 is a partly vertical section in a housing condition andFIG. 8 is a partly vertical section in a projecting condition. FIGS. 9and 10 show an example of the lock mechanism.

A penta-prism 114 is housed in a penta-house 112 provided at an upperportion of a single-lens reflex camera body 110. A housing chamber 116for housing a casing 120 of the built-in flash is provided in the upperfront of the penta-house 112. The housing chamber 116 has its upperportion opened for entrance of the casing 120. It is apparent from FIG.11 that a recess 116a for housing the penta-prism 114 is formed in thebottom center of the housing chamber 116. Further, link-housing chambers116b are formed at the opposite sides of the recess 116a.

The casing 120 has ceiling plate 122 which forms an outside appearancetogether with the penta-house 112 when the the casing 120 is in thehousing position, a bottom plate 123 corresponding to the recess 116a ofthe housing chamber 116, and side plates 124, one of which is shown,located in the opposite sides of the ceiling plate 122 and the bottomplate 123. A xenon tube (light emitter) 128 and a reflection mirror 130are housed in a light emission chamber 125 surrounded by the ceiling,bottom and side plates 122, 123 and 124. The reference numeral 126designates a diffusion plate for covering the front of the lightemission chamber 125.

A first turning lever 132 and a second turning lever 138 are pivoted attheir respective one ends on the outside surface of each side plate 124of the casing 120 through shafts 134 and 140, respectively. The shaft134 is disposed behind the center of the xenon tube 128 and the shaft140 is disposed at a rear lower portion. Further, the first turninglever 132 is pivoted at its other end on a shaft 136 disposed in anupper front portion of a side wall of the housing chamber 116, and thesecond turning lever 138 is pivoted at its other end on a shaft 142disposed in a lower rear portion of the same. The mechanism for poppingup the casing 120 is made up of a four-point linkage formed by the firstand second turning levers 132 and 138. The pair of first turning levers132 and the pair of second turning levers 138 are housed inlinkage-housing chambers 116b provided on the opposite sides of thehousing chamber 116, respectively. The pair of first turning levers 132are connected by a connection arm 133. The connection arm 133 acts tosecure the interlocking operation of the pair of four-point linkagemechanisms. The shaft 142 is disposed on an upper side surface of thepenta-prism 114. Each of the first turning levers 132 is L-shaped withineach of the linkage-housing chambers 116b, and the shaft 136 is disposedat the bent portion of the first turning lever 132.

When the casing 120 is in the housing position, the first turning levers132 are made substantially horizontal and the second turning levers 138are made frontward downward inclined to thereby hold the diffusion lens126 and hence the casing 120 downward. In the projecting position of thecasing 120, the second turning levers 138 are made substantiallyhorizontal and the first turning levers 132 are turned to positionswhere the first turning levers 132 are substantially vertical to therebyassure the height of the casing when projected.

A torsion spring 152 is interposed in the shaft 142 of the secondturning lever 138. One leg portion 152a of the spring 152 is engagedwith a projection 138a of the second turning lever 138 so that thesecond turning lever 138 is urged to move counterclockwise in thedrawing or in housing chamber 116.

It is apparent from FIG. 10 that the end portion of the shaft 142 isinserted into a side wall 118a of the housing chamber 116 as well asinto a supporting wall 118b at the inside thereof. A lock lever 150 isloosely put on the shaft 142 between the walls 118a and 118b so that thelock lever 150 can move in the axial direction of the shaft 142. Theother leg portion 152b of the torsion spring 152 is stop/engaged on aprojection 150b of the one end portion of the lock lever 150 so that thelock lever 150 is urged to move clockwise in the drawing normally. Theclockwise turning end is limited by contact with the inner wall of thehousing chamber 116.

The torsion spring 152 serves also as a compression spring, so that thelock lever 150 is elastically pressed toward the side wall 118a of thehousing chamber 116. However, as described above, the lock lever 150 isloosely put on the shaft 142 so that the lock lever can move or turnagainst the shift-direction force of the spring 152.

The stoppage/engagement surface at the top end of the lock lever 150 isformed as a wedge surface 150a having its lower portion expanded morethan the arc (shown by the one-dotted chain line of FIG. 9) with itscenter at the shaft 142. For example, the wedge surface 150a can beformed of an arc having its center lower than the shaft 152. When thecasing 120 is put in the housing chamber 116, the wedge surface 150africtionally touches a stoppage/engagement surface 132a of the firstturning lever 132 to prevent the first turning lever 132 from turningcounterclockwise. The wedge surface 150a and the stoppage/engagementsurface 132a have the relation that an edge 132b of thestoppage/engagement surface 132a comes into contact with a deeper(lower) point of the wedge surface 150a when the second turning lever ismoved downward. Accordingly, the stoppage/engagement prevents the secondturning lever 138 from turning counterclockwise due to the force of thetorsion spring 152, so that the casing 120 can be kept in the housingposition.

The engagement/disengagement between the lock lever 150 and the firstturning lever 132 is released by a push button 154 provided through theside wall 118a of the housing chamber 116. The push button 154 is linkedto an operation portion (not shown) projected out of the pentahouse 112.When the push button 154 is pushed down, the lock lever 150 is movedinward against the force of the torsion spring 152 by the top end of thepush button 154 facing the lock lever 150, so that the wedge surface150a is disengaged from the stoppage/engagement surface 132a.

A pair of switching members 149, each of which is composed of actuatingbar 144 and a contact 148, are provided at the opposite ends of thebottom of the housing chamber 116. The actuating bar has its top endformed as a projection 146 extending into the housing chamber. Theswitching member 149 serves as a switch of a flashlighting circuit. Whenthe casing 120 is in the housing position, the projection 146 is pressedby the second turning lever 138, so that the actuating bar isdisconnected from the contact 148 to open the circuit. On the contrary,when the casing 120 is in the projecting position, the second turninglever 138 is departed from the projection 146, so that the actuating baris in contact with the contact 148 to close the circuit. In this case,preparation for light emission of the built-in flash starts. The pair ofswitching members 149 are provided to secure switching operationsufficiently.

In the following, the operation of the pop-up mechanism of the secondembodiment will be described.

In the case where the built-in flash is to be used, the operationportion of the push button 154 in the housing condition of FIG. 7 ispushed down. As the result, the lock lever 150 is moved in the axialdirection of the shaft 142 so that the wedge surface 150a is disengagedfrom the stoppage engagement surface 132a. As the result, the secondturning lever 138 is moved counterclockwise by the turning force of thetorsion spring 152 so that the casing 120 linked to the second and firstturning levers 138 and 132 moves upward and forward to the projectingposition. In this projecting position, the second lever 138 is separatedfrom the protrusion 146 of the actuating bar 144 and the actuating bar144 is made to come into contact with the contact 148 to thereby closethe switch circuit to start the preparation of the strobe device.

In the case where the built-in flash is to be housed, the ceiling plate122 of the casing 120 is manually pushed by a finger. As the result, thecasing 120 is retracted into the hosing chamber 116 while the first andsecond turning levers 132 and 138 turn clockwise. A little before thecasing 120 reaches the housing position, the edge 132b of thestoppage/engagement surface 132a of the first turning lever 132 touchesthe wedge surface 150a of the lock lever 150 to start pressing down thelock lever 150. Accordingly, before the casing 120 reaches the housingposition, the edge 132b gets over the top portion of the wedge surface150a to engage with the wedge surface 150a. The frictional contactbetween the wedge surface 150a and the edge 132b of thestoppage/engagement surface 132a prevents the first turning lever 132from turning counterclockwise. When the casing is further pressed down,the wedge surface 150a of the lock lever 150 comes into frictionalcontact with the edge 132b of the stoppage/engagement surface 132 a at tdeeper point, so that the casing 120 is locked at this position.

Accordingly, any space is never produced between the ceiling plate 122and the housing chamber 116. Further, in the housing position, thesecond turning lever 138 pushes the projection 146 of the actuating bar144 to disconnect the actuating bar 144 from the contact 148 to therebybreak the flashlighting circuit.

It is apparent from the above description that the casing of the flashcan be moved between the projecting position and the housing position bya dimple linkage mechanism. Accordingly, the pop-up mechanism isadvantageous in that the workability in assembling is good, the numberof parts is small, and the operation is sure. In addition, it is easy tolocate the flash in a higher and more advanced projecting position.Accordingly, even in the case a long focal-length lens or a longfocal-length zoom lens having a long cylinder is used, light from theflash is never blocked by the cylinder.

Although the embodiment has shown the case where the lock lever 150 ismade to linearly move int he axial direction of the shaft 142, the locklever 150 may be made to move obliquely or flexuously.

The illustrated invention shows an example of the pop-up mechanism, butis not limited to the specific embodiment; it may be of course appliedwith equal utility to other pop-up mechanisms as long as the mechanismsare of the type in which the flash is kept in the housing position by alever turning with the pop-up operation of the flash and by a lock leverengaged with the lever.

In the pop-up device, a lock lever for locking the flash in the housingposition is provided with a wedge-action surface by which the flash canbe securely kept in the housing position by the wedge action.Accordingly, the flash can be kept in the housing position without idledistance due to a clearance of the stoppage/engagement portion.Consequently, the outside appearance of the camera is neverdeteriorated.

The conventional built-in flash has a light emission surface which lookstoward an object when the flash unit is in the projecting position. Therelation between the radiation angle of the flash and the camera lens issuch that as shown in FIG. 12. The range of radiation by the flashlightof the flash unit 250 is within an area between lines f1 and f2. On theother hand, the range of photographing by the camera lens 254 of thecamera body 252 is within an area between lines S1 and S2. Accordingly,the flashlight does not reach a hatched area in FIG. 12, that is, theflashlight does not reach a part of the area limited by the camera lens254. If photographing is carried out when the subject is nearer than theintersection a of lines f2 and S1, the film becomes partly underexposedbecause the flashlight never reaches the hatched area. This phenomenoncauses a problem particularly in macro photographing which has an aim ata close range.

Further, even if the flashlight was designed to reach such a neardistance, the film by macro photographing would become overexposedbecause the quantity of the flashlight can not be reduced from apredetermined value. This phenomenon causes a problem that properexposure is impossible in macro photographing.

These problems can be solved by widening the radiation angle of theflash. However, when the radiation angle is widened, a new problemarises in that far-distance photographing is limited.

Accordingly a third embodiment of the present invention is directed toan improvement in a built-in flash apparatus of a camera having a flashunit provided in a housing chamber provided at an upper portion of abody of the camera so that the flash unit is movable between a housingposition where the flash unit is housed in the housing chamber and aprojecting position where the flash unit is projected from the housingchamber, the improvement being characterized in that the flash unit hasa light emission surface which is directed forward in normalphotographing to look toward a subject when the flash unit is in theprojecting position and which is directed more downward in macrophotographing to look down to a subject when the flash unit is in thehousing position, in that a light-transmissible material is provided infront of the housing chamber, the light-transmissible material beingarranged to face the light emission surface when a light emitter ishoused in the housing chamber, and in that the flash unit is made to beable to emit light in the housing position as well as in the projectingposition.

Further, an ND filter or a diffusion lens may be used as thelight-transmissible material to reduce the quantity of light to therebyattain proper exposure.

The third embodiment will be described with reference to FIGS. 13 to 15.FIG. 13 and 14 are partial vertical sections respectively taken alongthe optical axis, showing a camera having a built-in flash as anembodiment according to the present invention. A penta-prism 214 ishoused in a penta-house 212 provided at an upper portion of asingle-lens reflex camera body 210. A housing chamber 216 for housing aflash unit 220 of the built-in flash is provided in the upper front ofthe penta-house 212.

The flash unit 220 is attached to the housing chamber 216 through aknown linkage mechanism by which the flash unit 220 can be moved betweena housing position (refer to FIG. 13) where the flash unit 220 is housedin the housing chamber 216 and a projecting position (refer to FIG. 14)where the flash unit 220 is projected from the housing chamber 216.

The flash unit 220 has a ceiling plate 222 which forms an outsideappearance together with the penta-house when the flash unit 220 is inthe housing position, a bottom plate 224 formed along the bottom of thehousing chamber 216, and side plates 226 for covering between theceiling plate 222 and the bottom plate 224. A Fresnel lens (converginglens) 230 acting as a light emission surface is attached to the front ofa light emission chamber 228 surrounded by the ceiling, bottom and sideplates 222, 224 and 226. A xenon tube 232 and a reflection mirror 234are housed in the light emission chamber 228. One of important points inthe present invention is that the Fresnel lens 230 is arranged to bedirected toward the subject in macro photographing when the flash unit220 is in the housing condition.

A linkage mechanism for popping up the flash unit 220 is providedbetween the walls of the housing chamber 216 and the side plates 226 atthe left and right of the flash unit 220. The structure in the left sideis the same as that in the right side, and therefore, the linkagemechanism will be described about one side, hereunder. First and secondlevers 236 and 238 are pivoted at their respective one ends relative tothe side plate 226 through shafts, and are pivoted at their other endsrelative to the penta-house 212 through shafts. In short, these leversand shafts constitute a four-point linkage mechanism.

A torsion spring (not shown) is attached to the second lever 238, sothat the second lever 238 is urged to move counterclockwise normally, orin other words the flash unit 220 is urged to move upward and forward.Further, a lock member (not shown) for keeping the flash unit 220 in thehousing position is provided in the second lever 238 and the penta-house212.

In addition to the aforementioned construction, a light-transmissibleplate 218 is provided in front of the housing chamber 216 so as to facethe Fresnel lens 230 in parallel when the flash unit 220 is in thehousing position. A transparent glass plate, a diffusion plate, an NDfilter, or the like, can be used as the light-transmissible plate 218.The angle of the light-transmissible plate 218 is adjusted so that anormal onto the light-transmissible plate 218 intersects the opticalaxis of the camera lens system, for example, at a middle point of thephotographing-enable distance in macro photographing.

Further, the built-in stroboscopic flash has a switch for permittinglight emission when the flash unit 220 is in the housing position.Although the conventional housing-type built-in stroboscopic flash cannot make light emission when housed, the flash according to the presentinvention can make light emission through he switch even when housed.

Therefore, the aforementioned built-in stroboscopic flash operates asfollows. In normal photographing, the flash unit 220 is kept in thehousing position as shown in FIG. 13 when unused. In use, the flash unit220 is projected to the usable position as shown in FIG. 14 by releasingthe stoppage/engagement of the lock member.

In macro photographing, light emission is made while keeping the flashunit 220 in the housing position. When light emission is made in thiscondition, light emitted from the xenon tube 232 passes through theFresnel lens 230 and light-transmissible plate 218 and then reaches theobject. The radiation by the flash is within an area between line F1 andF2 of FIG. 15. Accordingly, photographing with flashing can be made evenin the case where the subject is far from the intersection A of lines F2and S2. It is apparent from this fact how near the camera can beapproached to the subject by the light emission in the housingcondition, compared with the aforementioned fact that the radiation bythe flash unit 220 in the projecting position is within an area betweenlines f1 f2 of FIG. 13.

The invention, as to the mechanism for housing and projecting the flashunit 220, is not limited to the above specific embodiment. For example,the invention is applicable to the case where the rear end of the flashunit 220 is merely pivoted by a shaft.

Although the embodiment has shown the case where the flash unit 220 isprojected by the spring force, the flash unit 220 may be moved to theprojecting position and to the housing position by an electric motor.For example, this modification can be easily attained by providing a rowof gears linked to the electric motor, and a sector gear having itsrotational center in the first or second lever 236 or 238 and so as tobe engaged with the row of gears.

It is apparent from the above description of the invention that a flashunit having a light emission surface directed toward an object when theflash unit is in the housing condition is provided with alight-transmissible material provided in front of a housing chamber forhousing the flash unit so that flashing (light emission) can be madeeven in the case where the flash unit is housed in the housing chamber.Accordingly, it is possible to light the subject uniformly even in thecase of macro photographing. Further, an ND filter or a diffusion lensmay be used as the light-transmissible material in the built-in flash toreduce the quantity of light, so that proper exposure in macrophotographing can be attained easily.

A fourth embodiment of the present invention will be described withreference to FIG. 16. A top plate 311 is provided at the upper portionof a single-lens reflex camera. A flash unit housing chamber 312 isprovided on the top plate 311 so as to be located above a pentaprism ofthe top plate 311. A flash unit 315 is pivoted in the flash unit housingchamber 312 by a pair of shafts 313 disposed at the rear of the housing.The flash unit 315 has a light emission surface (Fresnel lens) 316 as afront surface. Known flash elements which are not shown, such as a lightemission tube, a reflector and the like, are provided within the flashunit 315. The flash unit 315 is arranged turnably round the shafts 313,so that the flash unit 315 is movable to the normal light emissionposition as shown by the two-dotted chain line in the drawing, thebouncing position as shown by the three-dotted chain line, and thehousing position as shown by the solid line. The normal light emissionposition is a position where the light emission surface 316 looksforward to the object. The housing position is a position where thelight emission surface 316 looks more downward than the direction towardthe object and where the flash unit is housed in the flash unit housingchamber 312. The bouncing position is a position where the lightemission surface 316 can move in a range from the normal light emissionposition to a position where the light emission surface 316 looks upwardperfectly. In the drawing, the position where the light emission surface316 looks upward perfectly is shown for convenience.

A sector gear 318 coaxially provided on the shaft 313 is fixed to a sideof the flash unit 315. The sector gear 318 is linked to a drive motor320 through a row of gears 319. Accordingly, when the drive motor 320 isreversibly operated, the flash unit can turn round the shaft 313 amongthe aforementioned three positions.

A code plate 322 for detection and control of the position of the flashunit 315 is fixed to a side of the sector gear 318. The code plate 322,in which the pattern is not shown, is in contact with brushes 323 and324 fixed to the top plate 311, so that not only the housing positionand the projecting position can be detected but also multistages of thebouncing position can be detected through the brushes 323 and 324.

When the aforementioned built-in flash is not used, the flash unit 315is moved to the position as shown by the solid line, by the drive motor320 to turn the light emission surface 316 more downward than thedirection toward the subject so that the flash unit 315 can be housed inthe flash unit housing chamber 312. In use, the drive motor 320 isoperated to move the flash unit 315 to the position as shown by thetwo-dotted chain line, so that the flush unit 315 can be projected. Forexample, a flash-projection signal, that is, a drive signal for thedrive motor 320, can be obtained by a flash-up switch not shown or by arelease button linked to a device for detecting brightness of thesubject. In other words, the flash unit 315 can be automaticallyprojected by pushing the release button by one stage in the case wherethe subject is dark. A stop signal to the normal light emission positioncan be obtained by a turn-position-detection signal from the brushes 323and 324 being in contact with the code plate 322. As described above,having projected at the normal light emission position, the flash unit315 waits for the completion of charge of the light emission circuit soas to enable photographing with flashing.

After completion of photographing with flashing, for example, the drivemotor 320 is reversed by any suitable means, such as re-operation of theflash-up switch, operation of another switch for housing the flash,generation of another switch for housing the flash, generation of asignal for detecting the human hand leaving go his hold of the releasebutton, or the like. As the drive motor 320 is reversed, the flash unitcan be housed in the flash unit housing chamber 312. The detection ofthe housing position and the stoppage of the drive motor 320 can be madein the same manner as described above, through the code plate 322 andbrushes 323 and 324.

On the other hand, in the case of bounce-photographing, the drive motor320 is continuously operated for example through a bounce-light emissionswitch. As the drive motor 320 is operated, the flash unit 315 movesfurther upward beyond the normal light emission position where the lightemission surface 316 looks toward the subject. Accordingly, if thephotographer releases the bounce-light emission switch when the angle ofthe light emission surface 316 becomes suitable, any suitable angle canbe selected. As the simplest method, it is possible to move the lightemission surface 316 automatically to the position of the three-dottedchain line where the light emission surface 316 looks most upward whenthe bounce-light emission switch is turned on.

As another operating method at bounce-photographing, a bounce-anglechangeover dial may be provided to set the angle of the flash unit 315so that the flash unit 315 can be turned by an angle set by the dial.Such control can be easily attained by the bounce-angle changeover diallinked to the code plate 322, the brushes 323 and 324, and the drivemotor 320.

After completion of the bounce-photographing, the flash unit 315 can bemoved to the housing position in the same manner as described above, bythe drive motor 320 through re-operation of the bounce-light emissionswitch, operation of another flash-housing switch or the like.

Although the embodiment has shown the case where the flash unit 315turns round the shafts 313 to any one of the housing position, thenormal light emission position and the bouncing position, linking means,such as four-bar linkage and the like, may be used as a mechanism formoving the flash unit 315. Any suitable means can be selected, if theflush unit 315 can be supported to turn the light emission surface 316forward (normal light emission position), downward (housing position)and upward (bouncing position) with respect to the subject and the flashunit 315 can be moved by the electric motor.

As described above, according to the this embodiment the flash unit canbe moved between the housing position and the projecting position by theelectric motor, so that any shock due to the movement of the flash unitbetween the projecting position and the housing position can be avoidedto thereby attain a desirable operational feeling. Further, the lightemission surface of the flash unit can be moved more upward than thedirection toward the subject to make bounce-photographing possiblewithout requiring any other outside flash. Accordingly, the capabilityof a single camera in photographic expression can be widened.

A fifth embodiment of the present invention will be described withreference to FIGS. 17 to 19. A top plate 411 is provided at the upperportion of a single-lens reflex camera. A flask unit housing chamber 413is provided on the top plate 411 so as to be located above a pentaprism412. Within the flash unit housing chamber 413, a ground plate 414 ishorizontally fixed to the rear portion of the flash unit housing chamber413. A pair of slide plates 415 are provided at opposite sides of theground plate 44 so as to be longitudinally slidable. A guide mechanismfor the slide plates 415 is composed of guide pins 416 respectivelyfixed onto opposite ends of the ground plate 414 so as to be differentfrom each other in position, and slots 416 respectively provided in theslide plates 415 to be fitted to the guide pins 416.

The pair of slide plates 415 are provided with racks 418 facing eachother. A pair of gears 419 having the same number of teeth and rotatablysupported on the ground plate 414 are respectively engaged with theracks 418. The gears 419 are engaged with each other. One of the gears419 is rotated by an electric motor 421 through a reduction gear row420. Accordingly, the pair of slide plates 415 move forward or backwardin the same direction when the electric motor 421 rotates forward orbackward.

The pair of slide plates 415 are respectively provided with upward-bentedges 422 between which a flash unit 424 is turnably supported by ashaft 423. The flash unit 424, which has no converging lens body, has alight emission surface 425 at its front portion and known flashelements, such as a light emission tube 426, a reflector 427 and thelike, housed int he flash unit 424.

A pair of cam plates 428 formed by bending upward are disposed onopposite sides of the ground plate 414. The cam plates 428 arerespectively provided with cam grooves 429 for controlling the attitudeof the flash unit 424. The cam grooves 429 are provided for insertion ofa pair of pins 430 projecting from sides of the flash unit 424 and, moreparticularly, each cam groove 429 is composed of a housing cam portion429a, a projecting cam portion 429b and an inclined cam portion 429c,the former two portions 429a and 429b being horizontal, the latterportion 429c being connecting the former two portions. When the pins 430are put into the corresponding housing cam portions 429a, the flash unit424 is housed in the flash unit housing chamber 413 with the lightemission surface 425 being turned downward. When the pins 430 are putinto the corresponding projecting cam portions 429b, the light emissionsurface 425 is turned round the shaft 423 so that the flash unit 424projects from the flash unit housing chamber 413 so as to face anobject.

An Fresnel lens plate (converging lens body) 432 to be disposed on thefront of the light emission surface 425 of the flash unit 424, has swingarms 433 extending backward from the opposite sides thereof. Bearingpins 435 are provided at the rear end portions of the swing arms 433 sothat the pivot pins 435 are rotatably supported into pivot holes 434 atthe side walls of the flash unit housing chamber 413.

The swing arms 433 of the Fresnel lens plate 432 are provided withinterlock slots 436 into which interlock pins 438 projecting from theopposite sides of the flash unit 424 are inserted. The interlock slots436 and the interlock pins 438 are arranged so as to locate the Fresnellens plate 432 in front of the light emission surface 425 in parallelwith the former when the flash unit 424 is in the housing position,while so as to interlockingly locate the Fresnel lens plate 432 in frontof the light emission surface 25 in parallel with the former when theflash unit turns to the projecting position (normal light emissionposition).

The aforementioned built-in flash according to this embodiment operatesas follows. Assume now that the flash is in the housing position asshown in FIGS. 18 and 19. One of the gears 419 directly linked to theelectric motor 421 is rotated in the direction of the arrow by theelectric motor 421, so that the other gear 419 rotates in the reversedirection. The pair of slide plates 415 move backward according to theengagement between the gears 419 and the racks 418. The flash unit 424which is rotatably supported by the shaft 423 at the upward-bent edges422 of the slide plates 415, also moves backward. The pins 430 of theflash unit 424 change their positions from the housing cam portions 429ato the inclined cam portions 429c of the cam grooves 429, so that theflash unit 424 moves round the shaft 423 to turn the light emissionsurface 425 upward. Finally, the pins 430 are put into the projectingcam portions 429b, so that the light emission surface 425 looks toward asubject correctly.

When the flash unit 424 moves upward, the interlock pins 438 implantedin the sides thereof also move upward. Accordingly, the Fresnel lensplate 432 locked by the interlock pins 438 and the interlock slots 436also moves round the pivot pins 435 upward to the front of the lightemission surface 425. Thus, preparation for flash-lighting has beencompleted.

When the slide plates 415 are further moved backward from thiscondition, the pins 430 of the flash unit 424 move within the projectingcam portions 429b and the interlock pins 438 move within the interlockslots 436. Accordingly, the distance l between the light emissionsurface 425 and the Fresnel lens plate 432 changes. As the distance lchanges, the radiation angle of the flashlight radiated from the Fresnellens plate 432 changes. That is, as the light emission surface 425becomes more distant from the Fresnel lens plate 432, the flashradiation angle becomes more narrow suitable to a telephotographic lens.On the contrary, when the light emission surface 425 approaches to theFresnel lens plate 432, a radiation angle suitable to a wide-anglephotographic lens can be attained.

When the electric motor 421 is reversed, the slide plates 415 moveforward. Accordingly, the flash unit 424 and Fresnel lens plate 432 movedownward in the reverse course to the aforementioned operation, so thatthe flash unit 424 returns to housing position as shown in FIG. 18.

For example, a flash exclusive switch may be provided for the switchingand rotational control of the electric motor 421 to move the flash unit424 from the housing position to the projecting position. Alternatively,a device for detecting the brightness of the subject and a releasebutton may be provided to be linked to each other so that the flash unit424 can be projected when the release button is half-pushed under thecondition in which the brightness takes a value not more than apredetermined value. For example, the distance l between the lightemission surface 425 and the Fresnel lens plate 432 in the normal lightemission position may be established by manual operation of a focallength establishing member or may be established by automatic operationin which the position of the slide plates is controlled by the electricmotor 421 according to focal-length information as long as thefocal-length information can be obtained electrically or mechanically.

As described above, according to the present invention, the radiationangle of the built-in flash can be changed. Accordingly, it is madepossible to adjust the radiation angle in accordance with the focallength of the camera lens. Further, the flash unit can be moved by theelectric motor, so that any shock due to the movement of the flash unitbetween the projecting position and the housing position can be avoidedto thereby attain a desirable operational feeling.

We claim:
 1. In a built-in flash pop-up device in which a flash isprovided in a housing chamber provided above a penta-prism in a body ofa camera so as to be movable between a housing position and a projectingposition by turning operation of a turning lever:a lock mechanism forlocking said built-in flash pop-up device characterized in that a locklever, having an engagement surface arranged to engage a stoppagesurface of said turning lever when said flash is moved to saidflash-housing position, is pivotally mounted to said housing chamber,and in that said lock lever is arranged to be moved in the axialdirection of a shaft of said turning lever so as to disengage saidengagement surface of said lock lever from said stoppage surface of saidturning lever.
 2. The built-in flash pop-up device according to claim 1,wherein said engagement surface of said lock lever is formed as a wedgesurface having a wedge function when said turning lever is moved towardsaid flash-housing position.
 3. In a built-in flash pop-up device inwhich a flash is provided in a housing chamber provided in a body of acamera so as to be movable between a housing position and a projectingposition by turning operation of a turning lever pivotable about anaxis, a lock mechanism for locking said built-in flash pop-up device,said lock mechanism comprising:a lock lever having an engagement surfacearranged to engage said turning lever when said flash is moved to saidhousing position, and means for moving said lock lever in a releasedirection substantially parallel to said axis so as to disengage saidengagement surface of said lock lever from said turning lever.
 4. Adevice according to claim 3, wherein said lock lever is biased in adirection opposite said release direction.
 5. A device according toclaim 3, wherein said lock lever is biased for pivoting in a firstdirection about a second axis and is pivoted about said second axis in asecond direction by said turning lever as said flash is moved from saidprojecting position to said housing position.
 6. A pop-up device for abuilt-in flash provided in a housing chamber provided in a body of acamera so as to be movable between a housing position and a projectingposition, said device including:a turning lever having a first surfaceand being pivotable in a first direction about an axis as said flash ismoved from said projecting position to said housing position andpivotable in a second direction about said axis as said flash is movedfrom said housing position to said projecting position; and a lock leverarranged to engage said turning lever when said flash is moved to saidhousing position, said lock lever having an inclined engagement surfacefor engaging said first surface of said turning lever at a plurality ofpositions of said flash; and biasing means for biasing said lock leverfor movement of said inclined surface toward said first surface.